Cryptarithms Online - Jorge Soares
Mathematical puzzles in which the digits are replaced by letters of the alphabet or other symbols. Brain-teasers by the author; cryptarithms from the journal Sphinx; a primer; books on cryptarithms, and links to relevant sites on the Web.
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Cryptoclub - Vera Pless, Janet Beissinger
This website includes tools to encrypt and decrypt messages, an
animated treasure hunt, a classroom message board to send and
receive encrypted messages, and a place to explore mathematics
topics related to cryptography, such as prime numbers and
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A Cryptographic Compendium - John Savard
A book about cryptography with information about a large number of cipher systems and a limited coverage of cryptanalysis. It is mostly concerned with the various kinds of ciphers people have used and only mentions a few things about breaking ciphers.
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Cryptography - Corey Reed
An introduction to cryptography, in particular affine enciphering applied to the alphabet, focusing on the use of linear algebra. Includes a primer on bases and modulus algebra and extensions for deciphering an affine enciphered message, using keys to
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Cryptonomicon.Net - Matthew S. Hamrick; PhP-Nuke
A community portal site for amateurs and professionals with an interest in cryptography. The site has some original content and news stories, but the Web links section (with over 1100 links to crypto and security related sites) is most interesting.
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CrystalMaker
A Macintosh program to display and manipulate all kinds of crystal structures. Using the free companion program, CrystalDiffract, CrystalMaker files can be used to generate x-ray and neutron powder diffraction patterns. Main features: In "Photo-Colour"
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CS22: Discrete Math - Brown University
An introduction to discrete math with a focus on proof, logic, proof by induction, cryptography and networks of processors: lessons, homework, solutions, and information. "Discrete mathematics" refers to the distinction between discrete sets (for example,
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CS Bits & Bytes - The National Science Foundation
CS Bits & Bytes highlights innovative computer science research, often at the intersection with other disciplines, and includes profiles of the individuals in the field, links for further exploration, and interactive activities. Past issues of the
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C++ Simulator of a Post Machine - Alex Vinokur
The program simulates Deterministic and Nondeterministic Multitape Post Machine. The following demo Post machines are demonstrated with using the C++ Simulator: an addition of one to a number (Deterministic, 1 tape), an addition of two numbers (Deterministic,
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C++ Simulator of a Turing Machine - Alex Vinokur
A program that simulates the deterministic and nondeterministic multitape Turing Machine. The following demo Turing machines are demonstrated with using the C++ Simulator: an addition program deterministic, 1 tape), an addition program with marker (deterministic,
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CSMC: Center for the Study of Mathematics Curriculum
An NSF-funded project serving the K-12 educational community by focusing scholarly inquiry and professional development around issues of mathematics curriculum. Major areas of work include understanding the influence and potential of mathematics curriculum
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CTAP Middle School Math Project - CTAP Region IV
A database of online technology resources supporting California middle school math content standards for grades 6, 7, and algebra. Designed for use in classroom instruction or as homework helpers for students, the matrices resources align to state standards
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C.T.J. Dodson - Christopher Dodson
Dodson provides notes and Maple or Mathematica packages for many different mathematics courses, including algebra and pre-calculus, calculus, differential equations, using computers for mathematics and statistics, and an introductory course on curves,
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Cube-It - Education Development Center, Inc. (EDC)
A math group activity: you will need fifty cubes per group. Gather sugar cubes, wooden cubes, units from Dienes blocks or Cusinaire rods, or any manipulative that has a cubical shape. Students will: estimate the dimensions of the largest cube that can
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Cube Roll - Cary and Michael Huang
Use the arrow keys to steer a cube along a path of squares towards a final square. Each successive level poses new restrictions based on which faces of the block can or cannot roll onto the square path, making a game out spatial thinking of polyhedral
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Cubes of Perfection - Ivars Peterson (MathTrek)
...Six is the smallest perfect number. Twenty-eight comes next. Its proper divisors are 1, 2, 4, 7, and 14, and the sum of those divisors is 28. Incidentally, if the sum works out to be less than the number itself, the number is said to be defective
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Cubeworld - Hank Gross
Cubeworld: an adventure in solid geometry. This book, with 21 illustrations by the author, is in the tradition of Edwin Abbott's classic Flatland and explores what might happen if the Earth were transformed into a cube. Gravity is different, rain falls
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CUNY Games Network - CUNY Academic Commons
Blog about the pedagogical uses of both digital and non-digital math games, how they improve student success, and how they encourage research and scholarship in the developing field of games-based learning. Posts, which date back to July, 2011, have included
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The Curious Creative: Maths - Tom Barrett
Blog by a former teacher and ICT Subject Leader. Barrett's math posts, which date to back to July, 2006, have included "Addressing the Balance: Multiflyer Times Tables Challenge," "Using Nintendo Wii Sports for Addition and Subtraction," "My Maths Lesson
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Curmudgeon
Blog by a veteran math teacher in Vermont who "believes that math should be taught, not collaboratively explored; algebra and geometry are better than a vague course of Integrated Math; spiraling doesn't work nearly as well as learning it properly the
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Curricula, Lessons, and Activities - ARTSEDGE
Annotated links on the Internet and additional offline resources highlighting lessons that interrelate the study of math with the arts. Organized into online curriculum, and related online resources of primary resources and indices.
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Curriculum - Math - Schoolinfosystem.org
"Curated education information" about mathematics curriculum. Posts reproduced from newspapers and other sources, which date back to April, 2004, have included "Math Teachers Speak Up"; "The Last Time You Used Algebra Was ..."; "Askey on Elementary Math
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Curriculum Pathways - SAS inSchool
Internet-based product that connects teachers to a broad range of curriculum resources and clarifies ways to use those resources in the classroom. Find lesson plans and links to Web sites in math, science, English, and social studies; access national
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